Imperative sentences are one of the four sentence types (declarative, interrogative, imperative, exclamative). The final punctuation is usually a full-stop/period (.) or an exclamation mark/point (!). Imperative sentences can be in positive or negative form, and can refer to present or future time. The usual function (job) of an imperative sentence is  to give a command or instruction. It tells us to do something. Although we use imperative sentences to give direct commands, we can also use them to give instructions more politely than a straight command. Instructions like this are quite common, for example in a user guide to explain how to operate a machine. Imperatives can also be used with words like "please" or "kindly" to add politeness. Remove the packaging. Open the blue box and connect the two wires. Please remain seated until the seatbelt sign is off. John sit down; the rest of you go home. Contributor: Josef Essberger, founder of EnglishClub.com. Originally from London, England, Josef is the author of several books for learners of English including English Prepositions List and Learn English in 7.